FILE – Professional NASCAR drivers use cars already are exempt from the Clean Air Act but North Carolina Republicans want a new law to ensure federal environmental regulations don’t hurt amateur drivers. This photo was taken at a slow shutter speed as crew members perform a pit stop on driver Jimmie Johnson's car during the NASCAR Sprint Cup series Coca-Cola 600 auto race at Charlotte Motor Speedway in Concord, N.C., Sunday, May 25, 2014. Terry RennaAP

FILE – Professional NASCAR drivers use cars already are exempt from the Clean Air Act but North Carolina Republicans want a new law to ensure federal environmental regulations don’t hurt amateur drivers. This photo was taken at a slow shutter speed as crew members perform a pit stop on driver Jimmie Johnson's car during the NASCAR Sprint Cup series Coca-Cola 600 auto race at Charlotte Motor Speedway in Concord, N.C., Sunday, May 25, 2014. Terry RennaAP

After a scare last year among auto racing fans that the federal Environmental Protection Agency might enforce a new anti-pollution regulation affecting the industry, some North Carolina Republicans in Congress want a new law to protect the sport.

Western North Carolina congressman U.S. Rep. Patrick McHenry filed a bill this week that would permanently block the EPA from regulating modified engines frequently used in amateur car racing. McHenry’s proposed legislation would amend the Clean Air Act to make race cars exempt from federal emissions standards on vehicles.

Professional drivers in NASCAR use cars that already are exempt from the Clean Air Act because those vehicle engines were not originally manufactured for use on public roadways.

The issue first emerged in early 2016 as the EPA rolled out a wide-ranging proposal related to fuel efficiency standards on commercial cars and regulations on aftermarket vehicle parts manufacturers. Federal officials maintained the intent of the proposal was never to start new enforcement on amateur racing but McHenry and other lawmakers pushed back, resulting in the EPA changing course in April 2016.

Other North Carolina co-sponsors on the bill include Republican U.S. Reps. Richard Hudson, Virginia Foxx, Walter Jones, Robert Pittenger, George Holding, Mark Meadows and David Rouzer. The bill has a total of 68 co-sponsors in the House, including eight Democrats from six states.

McHenry and Hudson tried last year to get a similar bill passed but the legislation got stuck in committee. U.S. Sens. Richard Burr and Thom Tillis, both North Carolina Republicans, introduced a companion bill in the Senate.

McHenry, who is a member of House Republican leadership as chief deputy whip, said he’s planning to work with President-elect Donald Trump’s incoming administration to make sure the “RPM Act” becomes law. The bill’s nickname comes from the long title “Recognizing the Protection of Motorsports Act.”